The Most Powerful TwoLetter Word in the World
by wrldpossibility
Summary: The first time Rick Castle hears the word 'no' from Kate Beckett, they're in mid-introduction.
1. Chapter 1

The Most Powerful Two-Letter Word in the World

The first time Rick Castle hears Kate Beckett say the word 'no', they're mid-introduction. She doesn't bother shaking his hand, never mind ask for an autograph. _"Sir,"_she implores the captain in an exaggerated hiss, "please!" and it's easy to tell it's the kind of 'please' that's asking for mercy, not requesting a gift of his presence.

He doesn't understand; he usually makes a splendid first impression.

As for himself, Rick thinks she's the most commanding detective in heels he's ever seen. Well, first he just thinks, _guh,_but he doesn't count that. (He's accustomed to being much more articulate.) So instead, he likens her to any number of fiery heroines before settling on one of his own creation.

It doesn't take him long to realize she'll never settle for one-dimensional. (And this suits him just fine.) And when he starts digging into her mother's case, it's the first time he's felt truly useful in a professional capacity in he doesn't know how long, so naturally, she throws it back in his face.

The summer Castle spends in the Hamptons is the longest of Kate's life. It's also the hottest on record for New York City, which just figures; she's sitting in a sweltering hell while he gallivants around the coast with that tramp of an agent. (Kate knows 'gallivanting' is just the right word, too.)

She spends the first month of it feeling nauseous every time she thinks of him (which is about once every 15.2 seconds, if she's being honest with herself, which obviously, she tries not to be). She lies awake at night, her bedroom window open to traffic noise and the rare breeze, and her mind wanders despite her best efforts: she constructs what a Castlesque Hampton retreat might look like, imagines a lot of mahogany and brass and glass windows open to the ocean air. She pictures tasteful decor, sand on the floor, sunrises viewed from bedrooms-and then, like the betrayer it is, her imagination turns to what might be going on inside those rooms, and the nausea is back, rolling through her like a wave.

By the second month, she's nursing her wounded pride (he hadn't told her 'no', exactly, but the sight of Gina sauntering up to him in the precinct had been a slammed door if she ever saw one), and by the third, she's build up enough resentment to be downright pissed off while mopping the sweat from her brow every other minute on the job.

By the time she surprises him mid-case in September, it feels damn good to be holding him at gunpoint.

Kate Beckett, the LA version, is all kinds of sexy. Not that Castle's surprised. Of course, there's more to it than that: it's the pleasure of seeing her with her hair down (figuratively and metaphorically), her feet bare, her badge off-if only for a few days. And then there's the very delicious proposition of sharing a hotel suite with her.

Not that _that_turns out quite as well as he'd expected. Maybe he'd been kidding himself, but for a minute or two there, he'd really thought-but no. She shuts him down just about as fast as she can, the door to any possible advancement of their relationship physically closing in his face.

On the plane ride home, he closes his eyes and drifts off with the assurance of her beside him, the faint scent of her shampoo in his nostrils, her body heat warm against his side. It's the best night's sleep he's ever had.

The minute Kate sees Castle step into the airplane hangar, she knows she's officially outnumbered. She also knows she can outrun him, outmaneuver him, and overpower him, but this, apparently, is where she is wrong.

She's not going down (or out) without a fight, and to her surprise, he gives her one. He wants her out of that hangar just as badly as she wants to be there, his will an unyielding force of vice-like grip and bracing strength. His hands encircling her biceps are every bit as inflexible, even while his words are near-soothing in her ear. "No!" she cries. "No, no, no, no, no," each syllable a muffled sob against the palm that presses tight to her mouth. She's never in her life had her will so utterly denied by a man, and the fact that it's at Rick's hand causes tears to fill her eyes and fall as she yells.

After the danger is gone and the hangar falls silent, she shoves him away from her, hard, only to meet with no resistance. He stumbles back under the power of her blow while she bends double at the waist, drawing huge gulps of air to curtail her sobs.

In the months following the shooting and her recovery, she jumps into her work with more zeal than ever. Maybe she makes arrests with more brutality than is strictly necessary, perhaps she yells more and listens less, maybe she bites off the heads of her detectives when they're not quick enough or smart enough for her, but she tells herself all this is temporary: for now, she needs to regain the upper hand any way she can.

She doesn't know whether Castle still feels the way he'd said he did that day of the shooting, and she doesn't ask. She can't afford to feel that vulnerable again, nor that victimized, should the answer be no. She remains stubbornly with Josh, if only to maintain the status quo, and when Castle hooks up with an art insurer following one of their toughest cases, she convinces herself this tells her all she needs to know.

She'd have believed herself, too, except that he doesn't leave. Through it all, he's obstinately by her side daily, in the precinct , on the streets. He rides shotgun and asks questions and puzzles out mysteries in his uniquely genius slash infuriating matter, same as ever.

He puts himself in danger's way same as ever, too. On a routine interview turned chase on Canal Street, he flattens a guy who'd been running toward her down a blind alley, and in SoHo, he pulls her own service piece from her holster while she's wrestling with a perp on the floor of a warehouse, shooting the guy clean through the shoulder just as he reaches for a knife hidden in his pant leg. (The paperwork on that one had brought new meaning to the phrase, 'late night at the office'.)

And every time, during every goddamn stunt he pulls, her heart feels as though it resides on the outside of her chest, for anybody to come by and stab. Her pulse races, her eyes follow him instead of the action around her, and she diverts her attention from wherever it's needed most...the victim, the danger to her team, in some cases, the barrel of the gun pointed in the direction of her own damned self...until one day she finds herself scrambling for a set of cuffs she should have easily secured all because she'd been trying to locate Castle in the midst of a firefight, and once she's reasonably sure they're not all going to die because of her, she finally thinks _enough_. She kicks him off the case effective immediately ("What'd _I_do?") and spends the rest of the afternoon wondering when she'd gone so soft.

The answer comes to her while she's turning the key in her lock late that night, and it's so reminiscent of a light bulb going off in her brain, she's almost blinded by the brilliance of it.

_Since she'd fallen in love with Castle, of course._

She's turned down his invitation to the Hamptons so many times, he hardly listens to the answer anymore. When this time, she says, "You know, Castle, maybe I will," he actually replies, "Maybe next time, then," prompting such an odd look on her face that he mentally rewinds their last few lines of conversation.

"Wait...maybe?"

"Maybe." She's still looking a little odd to him. In fact, she's been _acting_odd, too. Hesitant and ill-at-ease. Almost...polite. She's tossed him the car keys on occasion, and on cases, she's stopped discounting his theories; he'd even thrown in a werewolf-as-suspect as a test.

"Could be," she'd said.

Could be?

Maybe she knows something he doesn't: maybe he's dying and no one wants to tell him. What other explanation can there be? He decides that if she offers to take him to Disneyland, he'll schedule a full physical first.

He leaves for the Hamptons around noon on a Friday; Beckett is between cases, catching up on paperwork, Alexis is on an overnight school trip, his mother is in final rehearsals for a play, so nothing is holding him to the city. He's expecting to inot/i expect Beckett, but if she shows, it won't be until tomorrow, maybe Sunday (likely so she can avoid staying longer than a matter of hours).

He takes a long walk down the beach, not turning around until the sun has all but disappeared behind the roofline of the house. He gets a glass of water in the kitchen, during which he notices the slider door to the back deck is ajar. Details come easier to him these days; he knows immediately that it wasn't forced. He steps through it cautiously and out onto the deck, where he freezes. Beckett is standing at the rail, her back to him. He debates how to announce his presence without startling her until he sees her shoulder twitch under his scrutiny, and knows he hasn't surprised her at all.

"You came." He crosses to her, but something in her posture makes him stop a few feet down the rail, where he leans against the wood, watching her. He feels wary again, like a cat trying not to startle its prey. Or maybe it's the other way around. "To what do I owe this honor?"

He'd meant it in jest, of course, but she doesn't smile. In fact, she looks almost panicked.

She continues to stare ahead, her eyes on the black void that is the ocean at this hour. He can hear the waves rhythmically hitting the sand.

He immediately sobers. "What's wrong?"

"Nothing, I..." She swallows. "I've been called before a review board for the Shavez case misfire."

He answers slowly. "The one where I fired the shot?"

She nods, and he curses under his breath. "I'm sorry. Can I come with you, maybe explain-"

"No."

He bites his lip on a quick reply. Did she really come all the way out here to reprimand him? "Well, they're wasting their time and yours. You did everything by the book."

She shakes her head, exhales sharply. "Including letting him get the jump on me in the first place?"

"Listen, that happens..."

"When I'm distracted looking around for you, yes." She's speaking strangely calmly, considering that he's pretty sure (but not quite certain) they're in an argument. He wishes he could say the same for himself.

"Well I'm sorry I was in the way! Maybe you were outplayed because-"

"Rick..." Her voice has suddenly softened; she sounds almost saddened, and he finds himself falling silent. "I was outplayed because I love you." She's still staring ahead as her hands curl tightly on the rail.

_Because...?_

"And I need to know if you still love me." She's more rigidly focused on the ocean than ever, her shoulders square and unyielding. "Or if it's too late, and I've screwed it all up too badly."

He finds himself thinking for what must be the hundredth time that she's the bravest person he knows. He says, "No."

As straight and tense as she's standing, she still visibly flinches. "You haven't screwed it up," he continues. He's telling it to her profile; she still won't turn to look at him. "Of course I love you. More every damned day."

She breathes. He watches her chest rise and fall, and one corner of her mouth turn upward, then, as if still not willing to take the risk, back down into a frown as she closes her eyes tightly for a moment. Then she nods, eyes still on the black horizon.

He steps toward her, reaches out to her. "Kate." He cups her chin in one hand and tips her face toward him. In her eyes, he sees the pain caused by countless murders, misunderstandings, and bullets to the heart. (The line is corny even in his mind, but is too true to pass up.) He brings his face closer, then waits for her to be the one to close the distance.


	2. Chapter 2

The Most Powerful Two-Letter Word in the World, Part 2

Kate Beckett had always imagined that being in a relationship with Rick Castle would be a full-time job (and God help her, she'd imagined it plenty). As it turns out, their schedules are such that they see each other exactly twice in the week between their time in the Hamptons and her court date with internal affairs for the ill-fated Shavez case. The first time hardly counts, because technically, she doesn't even see him: he calls her the morning after they get back into the city, but she's already in the field, having been pulled from her bed at 4 am for what turns out to be a jumper. He can't talk either; he's been called into his publisher's office for a meeting with the supposed artist penning the Storm graphic novel (apparently the guy's been AWOL the last two months.)

The second time, he drops in at the 12th with her coffee per usual, only to be ushered right back out; until this Shavez thing is cleared, up, he's been benched. She doesn't hear from him all day, which she devotes almost entirely to worrying whether they can actually make this work, here amid the realism that is New York City. Perhaps what they had in the Hamptons was nothing more than a fluke...a spark of pent up _something_fueled only by escapism and too much fresh air. But when she turns the hall corner to her apartment door late that evening, he's waiting beside it, take-out boxes in hand, eyes twinkling. (She'd been starving, but interestingly enough, they don't get around to eating for over an hour.)

That night together in her bed is every bit as good (and is it ever) as either of the nights they'd spent together in the Hamptons, and Kate won't lie: she feels a little tendril of relief edge its way into her mind. She's no closer to figuring out how they're going to make this work, but at least she hasn't been imagining just how great it is.

Her hearing is two days spent in internal affairs hell, followed by a punishment of two weeks suspension, no pay. Castle takes it hard.

"What's _wrong_with those assholes?" he vents around a mouthful Monte Cristo sandwich at a deli on the corner of 14th and 7th. "Nothing better to do than push paper around, blow whistles? Someone should tell them no one likes a tattle tale."

Kate shrugs, mostly just glad it's over. Plus, Royce had always said that no self-respecting cop finishes out their career without having their hand slapped by internal affairs at least once or twice. (Or three times. Or five.) And honestly, what has her worried far more than a mark on her record is the prospect of spending fourteen days stewing in her apartment.

"Just spend them at the Hamptons house," Castle says, as if this this is the most obvious solution ever. She notes the _the_, as opposed to the _my_. As if what's his is already hers. (Which is probably exactly what he'd say should she question it.)

"I don't know..." But to her surprise (life is full of surprises these days), the prospect sounds...nice. More than nice. "Won't you be taking Alexis to college next week?"

He nods, undeterred. "Key's under the mat," he says, then waves away her horrified expression. "Oh, not really! It's a figure of speech. Anyway, I'll only be away the first week, then we can spend the second together before you're expected back." His foot touches her leg under the table, and that _feels_nice, too.

She finds herself smiling down at the table top like a teenager. "I'd like that."

Flying across the country with Alexis, Martha, and five of their biggest and costliest suitcases is one of the best times Castle's spent with the two of them, if emotionally exhausting. He gets Alexis set up in her dorm, meets her roommate (a perky volleyball player from Santa Barbara), pays off the boys on the floor below to steer clear of both of them, and then guides his mother out by one arm as she simultaneously blubbers on Alexis' shoulder and flirts with Perky Roomie's stockbroker dad. By the time they're flying back back home, he's in serious need of some R&R. Luckily for him, he knows just the place.

He'd worried that Kate would have trouble relaxing during her forced exile, but when he finds her at the Hamptons house, she's sprawled out on the sand on a beach blanket, the newest Gresham novel in one hand.

"I won't lie…the betrayal stings."

"Hey." She smiles up at him, squinting into the sun. "Betrayal?"

He indicates the book.

"Oh, it's terrible, actually. I keep telling myself I'm going to toss it right into the surf."

He might have believed her, but her eyes are already back on the page. "If only you could tear yourself away."

"Exactly." She grins guiltily. "Sorry, it's great."

Later, they're eating lobster tail and sipping a 1998 Riesling on the back deck while Castle fills her in on his week with Alexis.

"I've kept the fridge stocked," Kate says, "and had honorable intentions when the utility bill arrived in the mail, but decided, 'who was I kidding?' I just set it back on the front hall table."

"Kate. You're a guest here."

"I feel more like a squatter." She looks down at her glass, her finger absently toying with the rim. She lifts her gaze to the ocean and shifts gears: "It's so peaceful here. So far removed…like I'm in limbo."

"Do you feel that way?" If so, her inability to find her footing is a mutual thing. Considering their crazy schedules and external obligations, he wonders whether she's as unsure of where they are and where they're headed as he is. She doesn't answer right away, so he adds, "Do you _want_it to be that way?"

"What do you mean?"

"I mean what we have...it can stay between us, if you'd like. Here. Your place. Not at the 12th."

She scoffs. "Because you're a model of discretion." But there's something else in her expression that's harder to read.

"I can be." It pains him to say it; he has no interest in keeping her a secret from anyone.

Her mouth is tightening into a line. "Is that what you want?"

"You know it isn't."

She stands. "Ok then."

"Ok...wait-what?" Her retreat seems imminent; he stands as well, reaching for her hand on the plate she's attempting to clear. "Kate. I pushed my way into _your_life, not the other way around. I just want to respect those boundaries."

She actually laughs.

"Belatedly. I _belatedly_want to respect those boundaries."

"Well, stop it, alright? I've gotten used to you being my shadow."

They have a whole speech prepared, but as it turns out, no one at the precinct wants to hear it.

"About damn time," Esposito notes.

Ryan barely glances up from his phone. "You mean we may be subjected to some sexual tension around here? _That'd_be a change."

"And flirtatious bickering and stolen glances and-"

"Fine!" Kate seems more peeved about it than Castle. He just grins. "You guys win. Consider it to be business as usual around here."

"With benefits," Esposito whispers.

Turns out, business as usual includes a double-homicide, a gang-related drive by, and an open-and-shut robbery-gone-south all within the first month. The paperwork alone is enough to keep Beckett's mind of anything-and anyone-else.

As a result, Beckett's relationship with Castle progresses with all the haste of midtown traffic at rush hour...and that suits her just fine. The man's been married twice before: someone has to be the one to show some restraint instead of jumping in with both feet, and it's obviously not going to be him.

"The heart wants what the heart wants," he tells her, to which she's quick to reply:

"And wants...and wants...and wants?"

He tells her it's different this time, that in his case anyway, he finally knows what he wants: _has_ known, since he met her. And even though it sounds like a line-or perhaps _because_ of it...Castle would never use one-she believes him. She knows their love has been hard-won, knows the _getting here_has been test enough for both of them, and yet...the idea of going where other women have gone before-and failed-unnerves her more than she'd like to admit.

Perhaps because the stakes are so high.

Instead, she moves as cautiously as she would through a joint she's casing; each footfall measured, each move calculated. (And yes, she's been in enough relationships to know this isn't normal.) They date, but don't call it dating; they call it want-to-grab-something-to-eat-after-work, or how-about-I-buy-you-a-beer. She knows it drives Castle crazy-he's dying to call in a favor at whatever Zagat-rated bistro has the newest 'it' Manhattan chef-but she keeps circling, zagging when he zigs, ducking when he dives.

They spend weekends in the Hamptons when work permits, and weeknights at his place or her place-mostly his place-where they work side-by-side on laptops or in front of murder/characterization boards. The passion is there in spades, but it's tempered by a foundation of friendship and familiarity she's never experienced while dating a man before. She finds she likes it. It allows them to slide right past 'awkward first date' and 'will he call me' and 'I wish I knew what he was thinking' to some place much more comfortable, more secure, and more nurturing of a serious relationship.

Because she can tip-toe all she likes, but it _is_serious. As Nikki Heat would say, it's serious as hell.

Castle's been trying to get Kate to move into his loft for almost a month now. With Alexis at college and Martha-well, what does Martha care?-Kate's there nearly every night anyway. She won't admit to the Hypnos mattress or the Z Gallerie shower head or the Keurig coffee maker being superior, so he can only assume _he's_the draw. (Though if a French press would do the trick, he'd buy her one…and keep it at his place.) Still, every time he brings up the practicality of cutting her a key, she bristles.

"I have my own place, Castle."

"But my question is, why?"

She never has an answer, but always a look to give him: something between exasperation and panic. He doesn't like it.

"But we have different schedules. What if you want to come home, and I'm not around?"

She looks at him point blank. "Then I'll go _home,_, won't I?"

He frowns into his fair trade, organic, Blue Mountain blend. They've danced around this particular issue-and the larger one behind it-so many times, he could waltz with her in his sleep. He'd found it on the tip of his tongue to tell her that if he could erase the women of his past, he would, but that wasn't true, was it? Meredith had been all kinds of a mistake, but she'd given him Alexis. Gina was often a nightmare, but had chiseled away at many of the shaper edges of his personality that he'd not been proud of. As for the others...before, after, in-between...they were but dots on a map, points of interest that made him who he was once he met Detective Kate Beckett.

No other woman could-or ever had-held him like she did. No other woman would he be willing-eager!-to shadow, day after day, month after month. No other woman would he write for. No other woman would he be willing to die for.

It may be time to go over her head.

She's nearly made it to the end of a long day when her person of interest decides he'd rather be a person-in-lockup after assaulting her with a can of Diet Coke from the precinct vending machine. An _open_ can of Diet Coke. That _she'd_popped open and handed to him. It wouldn't have mattered-she has a spare shirt in her locker-except that she's supposed to go straight from work to an interview with a real estate mogul tangled up in a homicide in the Battery at six, and her retro Def Leppard tee is not the impression she wants to make.

She has exactly 45 minutes to make the meeting, and guess who's place is a) closer, and b) harboring the outfit she wants? Hint: it's not her own. She hails a cab which crawls toward SOHO while she and asks herself why she felt the need to move half her closet to the loft.

At the curb, she asks the cabbie to wait and crosses the sidewalk to the double glass doors of Castle's building. Bernie, the doorman, greets her with a wave and a "Good evening, Detective Beckett," as he opens the door. It's not until she's trotted halfway cross the lobby that she remembers Castle's not here: rather, he's about as far away as you can get, NYC-speaking, at a book signing in Brooklyn. She skids to a halt in front of the elevator bank, frozen in inaction.

Damn.

She tries his cell, in hopes he can authorize Bernie to let her in, but is patched straight through to voice mail. She tries Martha next, but gets an automated message from Verizon. Either she hasn't paid her bill, or has lost her charger. Or both.

She makes her way back to Bernie.

"Detective?"

She briefly considers flashing her badge, but seasoned doormen in Manhattan buildings like Castle's are not to be trifled with. Instead, she goes with charm. "I'm so sorry, I've got a cab waiting, and I'm hoping you can let me into the apartment." She smiled self-deprecatingly, indicating her stained shirt. "I'll only be a moment."

Bernie looked at her in confusion. "Have you lost your key, ma'am?"

"Oh I don't have one, I-"

"Yes you do." She frowns at him, but he's already turned toward his desk, where he's digging into a drawer. "Here it is."

Her knee-jerk reaction is to argue with him, an urge she quickly stifles in the name of self-preservation. Instead, she silently accepts it. "Mr. Castle had me make it weeks ago. Told me you'd be needing it eventually." His eyes crinkle as he smiles. "Said it was a waiting game."

She plans to give it back to him, but hadn't anticipated the satisfying sense of belonging turning the key in the lock later that night would garner. There was something about not knocking, not having to ask, that makes her wonder whether just maybe Castle had been right.

He smiles at her over the rim of his wine glass as she enters the kitchen. "How'd the interview go?" If he'd been surprised by her unaided entry, he doesn't show it.

She walks to the cabinet, grabs her own glass. "Fine. I had a crazy afternoon, though."

"Yeah?"

"Mmm." She's searching for something to eat in the fridge.

"Second shelf. Heat up the fettuccini."

She nods. "Perp tried to take me out with a soda. Had to come by and change." She grabs the leftovers, turns toward the microwave. "Interestingly, your man Burnie downstairs was able to help me out."

"How fortuitous. You know, I've always said he goes above and beyond-"

She turns to face him. "Rick?" Watches him swallow a gulp of wine, an argument clearly on the tip of his tongue. "Thank you."

She can practically see him shift mental gears. He smiles at her, and the warmth of it feels better than his glass-encased fireplace or his duel head massage shower. He tips his glass in her direction. "Welcome home."


End file.
